Characterization of Unbound Pavement Materials for Mechanistic-empirical Performance Prediction

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ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (247 download)

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Book Synopsis Characterization of Unbound Pavement Materials for Mechanistic-empirical Performance Prediction by : Gervas Wambura

Download or read book Characterization of Unbound Pavement Materials for Mechanistic-empirical Performance Prediction written by Gervas Wambura and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Characterization of Unbound Pavement Materials from Virginia Sources for Use in the New Mechanistic-empirical Pavement Design Procedure

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ISBN 13 :
Total Pages : 0 pages
Book Rating : 4.:/5 (672 download)

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Book Synopsis Characterization of Unbound Pavement Materials from Virginia Sources for Use in the New Mechanistic-empirical Pavement Design Procedure by : M. Shabbir Hossain

Download or read book Characterization of Unbound Pavement Materials from Virginia Sources for Use in the New Mechanistic-empirical Pavement Design Procedure written by M. Shabbir Hossain and published by . This book was released on 2010 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The implementation of mechanistic-empirical pavement design requires mechanistic characterization of pavement layer materials. The subgrade and base materials are used as unbound, and their characterization for Virginia sources was considered in this study as a supplement to a previous study by the Virginia Transportation Research Council. Resilient modulus tests were performed in accordance with AASHTO T 307 on fine and coarse soils along with base aggregates used in Virginia. The degree of saturation as determined by moisture content and density has shown significant influence on the resilient behavior of these unbound materials. The resilient modulus values, or k-values, are presented as reference for use by the Virginia Department of Transportation (VDOT). The results of other tests were analyzed for correlation with the results of the resilient modulus test to determine their use in estimating resilient modulus values. The results of the triaxial compression test, referred to as the quick shear test in AASHTO T 307, correlated favorably with the resilient modulus. Although the complexity of such a test is similar to that of the resilient modulus test for cohesionless coarse soil and base aggregate, fine cohesive soil can be tested with a simpler triaxial test: the unconfined compression test. In this study, a model was developed to estimate the resilient modulus of fine soil from the initial tangent modulus produced on a stress-strain diagram from an unconfined compression test. The following recommendations are made to VDOT's Materials Division: (1) implement the use of the resilient modulus test for pavement design along with the implementation of the MEPDG; (2) use the universal constitutive model recommended by the MEPDG to generate the k-values needed as input to MEPDG Level 1 design/analysis for resilient modulus calculation; (3) develop a database of resilient modulus values (or k-values), which could be used in MEPDG design/analysis if a reasonable material match were to be found; (4) use the initial tangent modulus from an unconfined compression test to predict the resilient modulus values of fine soils for MEPDG Level 2 input and the 1993 AASHTO design; and (5) continue to collect data for the unconfined compression test and update the prediction model for fine soil in collaboration with the Virginia Transportation Research Council. Implementing these recommendations would support and expedite the implementation efforts under way by VDOT to initiate the statewide use of the MEPDG. The use of the MEPDG is expected to improve VDOT's pavement design capability and should allow VDOT to design pavements with a longer service life and fewer maintenance needs and to predict maintenance and rehabilitation needs more accurately over the life of the pavement.

Characterization of Unbound Materials for Mechanistic-Empirical Pavement Design Guide (MEPDG)

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ISBN 13 :
Total Pages : 0 pages
Book Rating : 4.:/5 (14 download)

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Book Synopsis Characterization of Unbound Materials for Mechanistic-Empirical Pavement Design Guide (MEPDG) by : Jeyakaran Thavathurairaja

Download or read book Characterization of Unbound Materials for Mechanistic-Empirical Pavement Design Guide (MEPDG) written by Jeyakaran Thavathurairaja and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Mechanistic-empirical Pavement Design Guide

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Publisher : AASHTO
ISBN 13 : 156051423X
Total Pages : 218 pages
Book Rating : 4.5/5 (65 download)

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Book Synopsis Mechanistic-empirical Pavement Design Guide by : American Association of State Highway and Transportation Officials

Download or read book Mechanistic-empirical Pavement Design Guide written by American Association of State Highway and Transportation Officials and published by AASHTO. This book was released on 2008 with total page 218 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Effect of Subgrade Conditions on Pavement Analysis and Performance Prediction

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ISBN 13 :
Total Pages : 82 pages
Book Rating : 4.:/5 (128 download)

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Book Synopsis Effect of Subgrade Conditions on Pavement Analysis and Performance Prediction by : Md Jibon

Download or read book Effect of Subgrade Conditions on Pavement Analysis and Performance Prediction written by Md Jibon and published by . This book was released on 2019 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt: "The Mechanistic-Empirical (M-E) pavement design approach detailed in the Mechanistic-Empirical Pavement Design Guide (MEPDG), and subsequently implemented through AASHTOWare® Pavement ME Design relies extensively on detailed material properties that ultimately govern the analysis and performance prediction results. For unbound materials like soils and aggregates, Resilient Modulus (MR) is the most critical input parameter affecting layer response under vehicular and environmental loading. Representing a material’s ability to ‘recover’ after loading, resilient modulus is determined in the laboratory through repeated load triaxial testing. Although the original test protocol to measure the resilient modulus value of a soil or aggregate was developed back in the 1980’s, this test is still not widely used by state highway agencies because it is cumbersome, and requires significant investments towards equipment and personnel training. Accordingly, most agencies rely on correlation equations to predict the resilient modulus values for soils and aggregates from other easy-to-determine material properties. However, these correlation equations are mostly region specific, and therefore, do not produce adequate results across different geographic regions. This has led several state highway agencies to undertake local calibration efforts for improved prediction of material properties. Over the past decade, the Idaho Transportation Department (ITD) has invested significant resources to facilitate state-wide implementation of mechanistic-empirical pavement design practices. A research study was recently undertaken by ITD to develop a database of resilient modulus properties for different soils and aggregates commonly used in the state of Idaho for pavement applications. Another objective of the study was to assess the adequacy of different correlation equations currently available to predict soil and aggregate resilient modulus from easy-to-determine material (strength and index) properties. This Master’s thesis is based on tasks carried out under the scope of the above-mentioned project, and focuses on laboratory characterization and analysis of representative subgrade soil types collected from across Idaho. An extensive laboratory test matrix was developed involving commonly used mechanical and index tests, repeated load triaxial tests for resilient modulus determination, as well as tests to study the soil permanent deformation (plastic strain) behavior. Effect of moisture variation on soil strength, modulus, and permanent deformation properties was also studied by testing soil specimens at three different moisture contents. The test results were thoroughly analyzed to evaluate the feasibility of predicting resilient modulus from other material properties. Findings from this research effort have been documented in the form of two journal manuscripts. The first manuscript highlights the importance of using adequate subgrade resilient modulus values during pavement design. Eight different soil types were randomly selected from a total of sixteen soil types, and the corresponding laboratory test results were used to highlight the limitations of ITD’s current approach with assumed resilient modulus values. The second manuscript focuses on highlighting the importance of unbound material permanent deformation characterization during pavement design, and how small changes in moisture content can lead to significant differences in the rutting behavior of subgrade soils. First, a new permanent deformation testing protocol was developed to simulate typical stress states experienced by subgrade layers under vehicular loading. Subsequently, permanent deformation tests were carried out on subgrade soil types collected from two distinctly different regions in Idaho as far as annual precipitation is concerned. Tests were conducted at three different moisture contents to highlight how the rutting potential of the subgrade may change significantly based on site precipitation and drainage characteristics. Finally, recommendations were made regarding how state highway agencies can accurately represent resilient modulus properties of soils during pavement analysis and performance prediction using AASHTOWare® Pavement ME Design."--Boise State University ScholarWorks.

Review of the New Mechanistic-empirical Pavement Design Guide - a Material Characterization Perspective

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ISBN 13 :
Total Pages : 19 pages
Book Rating : 4.:/5 (775 download)

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Book Synopsis Review of the New Mechanistic-empirical Pavement Design Guide - a Material Characterization Perspective by :

Download or read book Review of the New Mechanistic-empirical Pavement Design Guide - a Material Characterization Perspective written by and published by . This book was released on 2005 with total page 19 pages. Available in PDF, EPUB and Kindle. Book excerpt: Characterization of pavement materials in the three hierarchical design levels of the proposed mechanistic-empirical pavement design (MEPD) guide involves application of the dynamic modulus technique for asphalt concrete and the resilient modulus for unbound materials. This approach, if adequately implemented, is expected to improve the road design processes. The advance design level recommends using actual laboratory test data of the dynamic and resilient modulus determined under simulated environmental and traffic loading conditions. To circumvent the need for conducting the mechanical test in lower design levels, predictive equations and correlations established with physical properties are used to estimate the mechanistic properties needed as input to the design software. This paper examines the simplifications incorporated in the model using results of dynamic and resilient modulus tests performed at the National Research Council Canada (NRC). For the covering abstract of this conference see ITRD number E211426.

Analysis of the Mechanistic-empirical Pavement Design Guide Performance Predictions

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ISBN 13 :
Total Pages : 44 pages
Book Rating : 4.:/5 (662 download)

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Book Synopsis Analysis of the Mechanistic-empirical Pavement Design Guide Performance Predictions by : Stacey D. Diefenderfer

Download or read book Analysis of the Mechanistic-empirical Pavement Design Guide Performance Predictions written by Stacey D. Diefenderfer and published by . This book was released on 2010 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Guide for Mechanistic-Empirical Design of New and Rehabilitated Pavement Structures (MEPDG) is an improved methodology for pavement design and the evaluation of paving materials. The Virginia Department of Transportation (VDOT) is expecting to transition to using the MEPDG methodology in the near future. The purpose of this research was to support this implementation effort. A catalog of mixture properties from 11 asphalt mixtures (3 surface mixtures, 4 intermediate mixtures, and 4 base mixtures) was compiled along with the associated asphalt binder properties to provide input values. The predicted fatigue and rutting distresses were used to evaluate the sensitivity of the MEPDG software to differences in the mixture properties and to assess the future needs for implementation of the MEPDG. Two pavement sections were modeled: one on a primary roadway and one on an interstate roadway. The MEPDG was used with the default calibration factors. Pavement distress data were compiled for the interstate and primary route corresponding to the modeled sections and were compared to the MEPDG-predicted distresses. Predicted distress quantities for fatigue cracking and rutting were compared to the calculated distress model predictive errors to determine if there were significant differences between material property input levels. There were differences between all rutting and fatigue predictions using Level 1, 2, and 3 asphalt material inputs, although not statistically significant. Various combinations of Level 3 inputs showed expected trends in rutting predictions when increased binder grades were used, but the differences were not statistically significant when the calibration model error was considered. Pavement condition data indicated that fatigue distress predictions were approximately comparable to the pavement condition data for the interstate pavement structure, but fatigue was over-predicted for the primary route structure. Fatigue model predictive errors were greater than the distress predictions for all predictions. Based on the findings of this study, further refinement or calibration of the predictive models is necessary before the benefits associated with their use can be realized. A local calibration process should be performed to provide calibration and verification of the predictive models so that they may accurately predict the conditions of Virginia roadways. Until then, implementation using Level 3 inputs is recommended. If the models are modified, additional evaluation will be necessary to determine if the other recommendations of this study are impacted. Further studies should be performed using Level 1 and Level 2 input properties of additional asphalt mixtures to validate the trends seen in the Level 3 input predictions and isolate the effects of binder grade changes on the predicted distresses. Further, additional asphalt mixture and binder properties should be collected to populate fully a catalog for VDOT's future implementation use. The implementation of these recommendations and use of the MEPDG are expected to provide VDOT with a more efficient and effective means for pavement design and analysis. The use of optimal pavement designs will provide economic benefits in terms of initial construction and lifetime maintenance costs.

Advances in Materials and Pavement Prediction

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Publisher : CRC Press
ISBN 13 : 042985580X
Total Pages : 596 pages
Book Rating : 4.4/5 (298 download)

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Book Synopsis Advances in Materials and Pavement Prediction by : Eyad Masad

Download or read book Advances in Materials and Pavement Prediction written by Eyad Masad and published by CRC Press. This book was released on 2018-07-16 with total page 596 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in Materials and Pavement Performance Prediction contains the papers presented at the International Conference on Advances in Materials and Pavement Performance Prediction (AM3P, Doha, Qatar, 16- 18 April 2018). There has been an increasing emphasis internationally in the design and construction of sustainable pavement systems. Advances in Materials and Pavement Prediction reflects this development highlighting various approaches to predict pavement performance. The contributions discuss links and interactions between material characterization methods, empirical predictions, mechanistic modeling, and statistically-sound calibration and validation methods. There is also emphasis on comparisons between modeling results and observed performance. The topics of the book include (but are not limited to): • Experimental laboratory material characterization • Field measurements and in situ material characterization • Constitutive modeling and simulation • Innovative pavement materials and interface systems • Non-destructive measurement techniques • Surface characterization, tire-surface interaction, pavement noise • Pavement rehabilitation • Case studies Advances in Materials and Pavement Performance Prediction will be of interest to academics and engineers involved in pavement engineering.

Asphalt Materials Characterization in Support of Implementation of the Proposed Mechanistic-empirical Pavement Design Guide

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ISBN 13 :
Total Pages : 45 pages
Book Rating : 4.:/5 (838 download)

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Book Synopsis Asphalt Materials Characterization in Support of Implementation of the Proposed Mechanistic-empirical Pavement Design Guide by :

Download or read book Asphalt Materials Characterization in Support of Implementation of the Proposed Mechanistic-empirical Pavement Design Guide written by and published by . This book was released on 2007 with total page 45 pages. Available in PDF, EPUB and Kindle. Book excerpt: The proposed Mechanistic-Empirical Pavement Design Guide (MEPDG) procedure is an improved methodology for pavement design and evaluation of paving materials. Since this new procedure depends heavily on the characterization of the fundamental engineering properties of paving materials, a thorough material characterization of mixes used in Virginia is needed to use the MEPDG to design new and rehabilitated flexible pavements. The primary objective of this project was to perform a full hot-mix asphalt (HMA) characterization in accordance with the procedure established by the proposed MEPDG to support its implementation in Virginia. This objective was achieved by testing a sample of surface, intermediate, and base mixes. The project examined the dynamic modulus, the main HMA material property required by the MEPDG, as well as creep compliance and tensile strength, which are needed to predict thermal cracking. In addition, resilient modulus tests, which are not required by the MEPDG, were also performed on the different mixes to investigate possible correlations between this test and the dynamic modulus. Loose samples for 11 mixes (4 base, 4 intermediate, and 3 surface mixes) were collected from different plants across Virginia. Representative samples underwent testing for maximum theoretical specific gravity, asphalt content using the ignition oven method, and gradation of the reclaimed aggregate. Specimens for the various tests were then prepared using the Superpave gyratory compactor with a target voids in total mix (VTM) of 7% ± 1% (after coring and/or cutting). The investigation confirmed that the dynamic modulus test is an effective test for determining the mechanical behavior of HMA at different temperatures and loading frequencies. The test results showed that the dynamic modulus is sensitive to the mix constituents (aggregate type, asphalt content, percentage of recycled asphalt pavement, etc.) and that even mixes of the same type (SM-9.5A, IM-19.0A, and BM 25.0) had different measured dynamic modulus values because they had different constituents. The level 2 dynamic modulus prediction equation reasonably estimated the measured dynamic modulus; however, it did not capture some of the differences between the mixes captured by the measured data. Unfortunately, the indirect tension strength and creep tests needed for the low-temperature cracking model did not produce very repeatable results; this could be due to the type of extensometers used for the test. Based on the results of the investigation, it is recommended that the Virginia Department of Transportation use level 1 input data to characterize the dynamic modulus of the HMA for projects of significant impact. The dynamic modulus test is easy to perform and gives a full characterization of the asphalt mixture. Level 2 data (based on the default prediction equation) could be used for smaller projects pending further investigation of the revised prediction equation incorporated in the new MEPDG software/guide. In addition, a sensitivity analysis is recommended to quantify the effect of changing the dynamic modulus on the asphalt pavement design. Since low-temperature cracking is not a widespread problem in Virginia, use of level 2 or 3 indirect tensile creep and strength data is recommended at this stage.

Local Calibration of Material Characterization Models for Performance-based Flexible Pavement Design

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ISBN 13 :
Total Pages : 0 pages
Book Rating : 4.:/5 (135 download)

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Book Synopsis Local Calibration of Material Characterization Models for Performance-based Flexible Pavement Design by : Alexander Afuberoh

Download or read book Local Calibration of Material Characterization Models for Performance-based Flexible Pavement Design written by Alexander Afuberoh and published by . This book was released on 2018 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Mechanistic Empirical Pavement Design Guide (MEPDG) method, currently known as Pavement ME, recommends using locally calibrated material characterization models developed from laboratory testing of local materials under specific environmental and traffic loading conditions. The Pavement ME design method offers a more realistic design procedure and reduces the uncertainty that arise from empirical design procedures. This thesis developed a locally calibrated indirect tensile (IDT) strength material model for low temperature cracking predictions of hot mix asphalt (HMA) in Manitoba, Canada. In addition, the research investigated the integration of locally calibrated HMA, and unbound granular material characterization models into the Pavement ME framework to improve the design of flexible pavements. Laboratory IDT testing was conducted on typical HMA mixtures containing extracted binders and varying percentages of reclaimed asphalt pavement (RAP). The laboratory measured IDT strengths were used to calibrate a local IDT strength predictive model for Manitoba. The predictions from the local Manitoba model were compared to the predictions from the global Pavement ME IDT model, and a Michigan calibrated IDT model, using a statistical analysis. It was found that the global Pavement ME IDT strength model, if used without local calibration, produced inaccurate predictions of the IDT strength for Manitoba mixtures. It was also found that binder characterization methods in Level 2 and Level 3 can significantly impact the accuracy of IDT strength predictions. A case study using developed local HMA, base, and subgrade material characterization models in Manitoba were compared to designs using default (Level 3) material input values in Pavement ME design software. The results of integrating the locally calibrated models for HMA, base and subgrade layers demonstrated that the locally calibrated materials model inputs produce lower pavement structural thicknesses with higher reliability in the predicted distresses when compared to the default materials inputs. The effect of using calibrated material inputs was more pronounced for higher traffic loadings. The results of the study demonstrate that the use of calibrated models can potentially produce optimized pavement thicknesses due to improved pavement designs.

Unbound Granular Materials

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ISBN 13 :
Total Pages : 231 pages
Book Rating : 4.:/5 (957 download)

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Book Synopsis Unbound Granular Materials by : A. Gomes Correia

Download or read book Unbound Granular Materials written by A. Gomes Correia and published by . This book was released on 1999 with total page 231 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Estimating Stiffness of Subgrade and Unbound Materials for Pavement Design

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Publisher : Transportation Research Board
ISBN 13 : 0309098114
Total Pages : 139 pages
Book Rating : 4.3/5 (9 download)

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Book Synopsis Estimating Stiffness of Subgrade and Unbound Materials for Pavement Design by : Anand J. Puppala

Download or read book Estimating Stiffness of Subgrade and Unbound Materials for Pavement Design written by Anand J. Puppala and published by Transportation Research Board. This book was released on 2008 with total page 139 pages. Available in PDF, EPUB and Kindle. Book excerpt: At head of title: National Cooperative Highway Research Program.

Paving Materials and Pavement Analysis

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Publisher : Amer Society of Civil Engineers
ISBN 13 : 9780784411049
Total Pages : 592 pages
Book Rating : 4.4/5 (11 download)

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Book Synopsis Paving Materials and Pavement Analysis by : American Society of Civil Engineers

Download or read book Paving Materials and Pavement Analysis written by American Society of Civil Engineers and published by Amer Society of Civil Engineers. This book was released on 2010 with total page 592 pages. Available in PDF, EPUB and Kindle. Book excerpt: Pavement Design And Paving Material Selection are important for efficient, cost effective, durable, and safe transportation infrastructure Paving Materials and Pavement Analysis contains 73 papers examining bound and unbound material characterization, modeling, and performance of highway and airfield pavements. The papers in this publication were presented during the GeoShanghal 2010 International Conference held in Shanghai, China, June 3-5, 2010.

Implementation of the AASHTO Mechanistic-empirical Pavement Design Guide and Software

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ISBN 13 :
Total Pages : 84 pages
Book Rating : 4.:/5 (1 download)

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Book Synopsis Implementation of the AASHTO Mechanistic-empirical Pavement Design Guide and Software by :

Download or read book Implementation of the AASHTO Mechanistic-empirical Pavement Design Guide and Software written by and published by . This book was released on 2014 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt: Introduction -- Mechanistic-Empirical Pavement Design Guide and AASHTOWare Pavement ME Design (TM) Software Overview -- Survey of Agency Pavement Design Practices -- Common Elements of Agency Implementation Plans -- Case Examples of Agency Implementation -- Conclusions.

AASHTO Guide for Design of Pavement Structures, 1993

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Publisher : AASHTO
ISBN 13 : 1560510552
Total Pages : 622 pages
Book Rating : 4.5/5 (65 download)

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Book Synopsis AASHTO Guide for Design of Pavement Structures, 1993 by : American Association of State Highway and Transportation Officials

Download or read book AASHTO Guide for Design of Pavement Structures, 1993 written by American Association of State Highway and Transportation Officials and published by AASHTO. This book was released on 1993 with total page 622 pages. Available in PDF, EPUB and Kindle. Book excerpt: Design related project level pavement management - Economic evaluation of alternative pavement design strategies - Reliability / - Pavement design procedures for new construction or reconstruction : Design requirements - Highway pavement structural design - Low-volume road design / - Pavement design procedures for rehabilitation of existing pavements : Rehabilitation concepts - Guides for field data collection - Rehabilitation methods other than overlay - Rehabilitation methods with overlays / - Mechanistic-empirical design procedures.

Materials Characterization and Analysis of the Marquette Interchange HMA Perpetual Pavement

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ISBN 13 :
Total Pages : 106 pages
Book Rating : 4.3/5 (555 download)

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Book Synopsis Materials Characterization and Analysis of the Marquette Interchange HMA Perpetual Pavement by :

Download or read book Materials Characterization and Analysis of the Marquette Interchange HMA Perpetual Pavement written by and published by . This book was released on 2008 with total page 106 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Anisotropic Characterization and Performance Prediction of Chemically and Hydraulically Bounded Pavement Foundations

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ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (689 download)

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Book Synopsis Anisotropic Characterization and Performance Prediction of Chemically and Hydraulically Bounded Pavement Foundations by : Reza Salehi Ashtiani

Download or read book Anisotropic Characterization and Performance Prediction of Chemically and Hydraulically Bounded Pavement Foundations written by Reza Salehi Ashtiani and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The aggregate base layer is a vital part of the flexible pavement system. Unlike rigid pavements, the base layer provides a substantial contribution to the load bearing capacity in flexible pavements, and this contribution is complex: stress dependent, moisture dependent, particle size dependent, and is anisotropic in nature. Furthermore, the response of the aggregate layer in the pavement structure is defined not only by resilient properties of the base layer but also by permanent deformation properties of the aggregate layer. Before the benefits of revolutionary changes in the typical pavement structures, such as deep unbound aggregate base (UAB) layers under thin hot mix asphalt surfaces and inverted pavement systems can be justified, an accurate assessment of the UAB is required. Several researchers identified that in order to properly assess the contribution of the UAB in the pavement structure, it is necessary to consider not only the vertical modulus but also the horizontal modulus as this substantially impacts the distribution of stresses within the pavement structure. Anisotropy, which is defined as the directional dependency of the material properties in unbound granular bases, is inherent even before the aggregate layer is subjected to traffic loads due to random arrangement of particles upon compaction. Distribution of particle contacts is dominated by the geometry of the aggregates as well as the compaction effort at the time of construction. Critical pavement responses and therefore performance of flexible pavements are significantly influenced by the level of anisotropy of aggregate layers. There are several ways to characterize the level of anisotropy in unbound aggregate systems. Previous research at Texas A & M University suggests functions of fitting parameters in material models (kvalues) as characterizers of the level of anisotropy. In the realm of geotechnical engineering, the ratio of the horizontal modulus to vertical modulus is commonly referred to as the level of anisotropy. When the vertical and horizontal moduli are equal, the system is isotropic, but when they differ, the system is anisotropic. This research showed that the level of anisotropy can vary considerably depending on aggregate mix properties such as gradation, saturation level, and the geometry of the aggregate particles. Cross anisotropic material properties for several unbound and stabilized aggregate systems were determined. A comprehensive aggregate database was developed to identify the contribution level of aggregate features to the directional dependency of material properties. Finally a new mechanistic performance protocol based on plasticity theory was developed to ensure the stability of the pavement foundations under traffic loads.